there are plenty of options for those species at both places mate

any time of year is good for the montes however july - sep usually brings the easterlies and they can be a pain.

the only real benefit to going to the montes is probably a little more diverse and offers some more protection if the wind really sets in, still plenty of options in those circumstances

if your into sport fishing then i dont think you could go wrong either way mate

I'm looking into a Rowley trip next year. I think the diversity really stands out.

Both are pretty good areas. Not had the chance to do Rowleys yet but is on the list for next year.
I was at montes last weekend. Blew hard all weekend and we still caught loads of fish. So many options available if the weather is bad.

I've been to both and would say the Montebello's are better for diversity. There are more options if the weather turns bad, more shallow water fishing, there is still game fishing if that's your thing, plus there are islands and historical sights to visit.
If pelagics and gamefishing is all you want to do then pick the Rowleys, there is also some decent areas for shallow water lagoon fishing but there is heaps of the reef that is closed to fishing. There is also less options if the weather goes bad.

Coral trout, spanglies, red emps, rankins, mackies, mangrove jacks, GT's, crays- go the Monties.

Sails, wahoo, dogtooth, some trout, GT's- go the Rowleys.

Having said that I would pay for a charter to both places at the drop of a hat, you really just need to decide what you want to do more.

We have just booked the montebello's for next year June 27 -5 july should be great .Lets hope I don't get all fished out in Exmouth in Aril.

I done the montes 8 or 9 times and rowleys twice either has its benefits i was lucky enough to have a mate in onslow with a charter boat so we got mates rates about $700 for a week from memory and also a mate in point samson has a trawler so we got the rowleys cheap about $1200 for two weeks if you plan on taking a charter to rowleys then be prepared to fork out some $$$$$ but it is worth it we went to imperrieuse reef and the diving,jigging trolling and bottom fishing is second to none .we went in october and i think the wind stayed a constant 10 to 15 kn except for once when the wind got to 30 to 35 kn easterly for two days and we had to anchor on the west side just behind the breakers didnt get much sleep  for two days listening to waves break and the anchor dragging isnt what you want.montes has the option of shallow water fishig if the wind gets up the best weather we had was in sept and for fishing as well we had sailys chasing our bottom rigs to the bottom one bloke actuaally caught one on a squid head so we didnt do much trolling just floaters out the back done the job good diving as well couple of boys got stung up on big jacks ,trout spanglies.plenty of fishing off the beach with some stonker whiting for breakfast is also good so plenty options at both places either one you choose you will do well.

rowleys red bass,4-5 different types of trout ,maori emperor cods south african snapper maori wrasse heaps trevally dogtooth wahoo sails marlin mackies and shit loads more reckon broadbill as well but we didnt try

Montes trout spanglies mackies jacks crays reds rankins chinaman whiting muddies sails marlin shit loads more

It's a bit of no-brainer for me... I'd definitely choose Rowleys over a trip to the Montes. Went to the Rowleys in '08 and it was awesome, soooo much variety and plenty of stuff that aren't as common closer to the mainland. Big dogtooth, GTs, sails, wahoo, more trout than you can poke a stick at, maori wrasse, red bass, bluefin trevs... plus heaps more. Heaps of options when the wind blows, you've got truckloads of fishing inside the lagoon at clerke and the lee side of the shoal is generally calm, and easy to troll, pop, jig etc even when it's blowing.